Automatically resolve MS<->ddf solution naming conflicts for LoTSS subtraction

This a a copy of RAP-461 on the ASTRON Jira board.

Description

The way sub-sources-outside-region / DDFacet matches solutions to MeasurementSets for the LoTSS subtract is by name. Therefore the MS that go into the subtract workflow and the solutions in SOLSDIR need to be matched in name. This should be done automatically such that no manual renaming of either is required.